Rectal prolapse due to Gastrophilas intestinalis larvae in a horse: A case report

Abstract

Rectal prolapse in equine generally results from prolonged tenesmus or other conditions that cause proctitis such as bot larvae infection of the rectal mucosa, diarrhea, constipation or false copulation. A six year old stallion with rectal prolapse was brought to the local veterinary hospital in January 1989. The prolapsed part was 10 cm long in which four clusters of 8-12 reddish colored larvae were attached to the mucosa. These larvae were having twelve segments of which the first two were fused together and two brown hooks were present, but there was no head. The posterior stigmata opened through semi-circular plates. The dorsal surface of the larvae had complete row of spines on segments two to eight. Spines of the first row were larger than spines of the second row. The larvae were classified to the genus. Gastrophilus, species G. Intestinalis. The pathogenesis of G. intestinalis larvae is related to inflammatory process where these larvae attach themselves. In few cases stomach